Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of the common general knowledge in the field.
Information retrieval is an established field of technology that often seeks to solve the problem of identifying the optimal set of documents, for example a search result, that solves an information need described by a query. Where identifying the optimal set of documents usually involves the steps of first determining the set of relevant documents and then ranking the identified documents by how likely they are to resolve the information requested by the query.
Related technologies, such as clustering, query expansion, sub-topic identification and hierarchical faceted navigation, are further utilised as supplemental tools which are typically aimed at enhancing the ability of users to identify specific information from within a defined closed set of documents.
These technologies are each limited in their ability to either define an optimal set of documents or to identify related information based on a provided search query.